Genetic Links Seen Between Bipolar Illness and Schizophrenia

Certain genetic variants are associated with both conditions, study shows

Please note: This article was published more than one year ago. The facts and conclusions presented may have since changed and may no longer be accurate. And "More information" links may no longer work. Questions about personal health should always be referred to a physician or other health care professional.

THURSDAY, Sept. 22, 2011 (HealthDay News) -- There is a genetic link between schizophrenia and bipolar disorder, two common and often disabling brain disorders, a new study indicates.

Researchers identified 11 genetic regions, including six that had never been discovered before, which play a role in people's risk for these mental illnesses. The findings, they say, provide new insight into the causes of both conditions.

"Schizophrenia and bipolar disorder are debilitating illnesses affecting millions of people around the world, and existing therapies for these people are ineffective as long-term options," the bipolar study's lead author Dr. Pamela Sklar, chief of the division of psychiatric genomics in the department of psychiatry and a professor of psychiatry at Mount Sinai School of Medicine, said in a news release. "We have been hard at work trying to determine genetic risk for these diseases so that we can intervene earlier and develop new therapies with which to treat them. Through this research, we are an important step closer to making that possible."

Researchers examined the DNA of 7,481 people with bipolar disorder as well as 9,250 healthy people. In a separate study, another team of scientists evaluated the same DNA sites in more than 17,000 people with schizophrenia.

In these two studies, the researchers found several DNA sites also known as DNA variants in certain genes were linked with schizophrenia and bipolar disorder. In some cases, certain variants were associated with both disorders. They argued the findings could help scientists identify new treatments for these mental illnesses enabling them to treat them earlier on and more effectively.

"Until recently, psychiatric research has understood the genetic basis of mental illness only very poorly," Dr. Shaun Purcell, an associate professor of psychiatry at Mount Sinai School of Medicine and co-author on the schizophrenia study, said in a news release. "Our research has helped us begin to elucidate the genetic structure of bipolar disorder and schizophrenia, and will, we hope, provide a new foundation to build upon in improving treatments and the quality of life of these patients."